CVE-2025-10123 Overview
A command injection vulnerability has been identified in D-Link DIR-823X routers running firmware versions up to 250416. The vulnerability exists in the sub_415028 function within the /goform/set_static_leases endpoint, where improper handling of the Hostname argument allows attackers to inject and execute arbitrary system commands. This flaw can be exploited remotely without authentication, potentially allowing threat actors to gain unauthorized access to the affected network device.
Critical Impact
Remote attackers can exploit this command injection vulnerability to execute arbitrary commands on affected D-Link DIR-823X routers, potentially compromising the entire network infrastructure and enabling further lateral movement.
Affected Products
- D-Link DIR-823X Firmware (versions up to 250416)
- D-Link DIR-823X Hardware
Discovery Timeline
- 2025-09-09 - CVE-2025-10123 published to NVD
- 2025-09-24 - Last updated in NVD database
Technical Details for CVE-2025-10123
Vulnerability Analysis
This vulnerability is classified as CWE-74 (Improper Neutralization of Special Elements in Output Used by a Downstream Component), commonly referred to as injection. The flaw resides in the firmware's web management interface, specifically in how the router processes DHCP static lease configuration requests.
When a user or attacker sends a request to the /goform/set_static_leases endpoint, the sub_415028 function processes the Hostname parameter without adequate input sanitization. This allows specially crafted input containing shell metacharacters or command sequences to be passed directly to system command execution functions, enabling arbitrary command injection.
The vulnerability is particularly concerning because it can be exploited remotely over the network without requiring any authentication. This means any attacker with network access to the router's management interface can potentially execute commands with the privileges of the router's firmware process.
Root Cause
The root cause of this vulnerability is insufficient input validation and sanitization in the sub_415028 function. The function fails to properly escape or filter special characters in the Hostname argument before incorporating it into system commands. This is a common vulnerability pattern in embedded device firmware where user-supplied input is concatenated directly into shell commands without proper neutralization of command injection sequences.
Attack Vector
The attack can be launched remotely over the network by sending malicious HTTP requests to the router's web management interface. An attacker would craft a request to the /goform/set_static_leases endpoint with a manipulated Hostname parameter containing command injection payloads. Common injection techniques include using shell metacharacters such as semicolons, backticks, or command substitution syntax to append malicious commands that execute alongside the intended operation.
The exploit has been publicly disclosed, and technical details are available in the referenced GitHub PoC Repository. Attackers targeting this vulnerability would typically attempt to establish a reverse shell, extract sensitive configuration data, or modify router settings to facilitate further network compromise.
Detection Methods for CVE-2025-10123
Indicators of Compromise
- Unusual HTTP POST requests to /goform/set_static_leases containing shell metacharacters (;, |, `, $()) in the Hostname parameter
- Unexpected outbound connections from the router to external IP addresses
- Modifications to router configuration files or startup scripts
- Presence of unauthorized user accounts or SSH keys on the device
- Anomalous process execution on the router such as wget, curl, or netcat spawned by the web server process
Detection Strategies
- Implement network intrusion detection rules to monitor for suspicious HTTP requests targeting /goform/set_static_leases with potentially malicious payloads
- Deploy web application firewall (WAF) rules to block requests containing command injection patterns in form parameters
- Monitor router logs for failed or unusual authentication attempts and configuration changes
- Establish baseline network behavior and alert on deviations in traffic patterns originating from network devices
Monitoring Recommendations
- Enable comprehensive logging on the D-Link DIR-823X and forward logs to a centralized SIEM solution for analysis
- Configure network monitoring to detect unexpected DNS queries or outbound connections from router management interfaces
- Implement periodic integrity checks of router configuration against known-good baselines
- Set up alerts for any firmware or configuration modifications on network infrastructure devices
How to Mitigate CVE-2025-10123
Immediate Actions Required
- Restrict access to the router's web management interface to trusted internal networks only; do not expose it to the internet
- Implement network segmentation to isolate management interfaces from general network traffic
- Configure firewall rules to block external access to the router's administrative ports
- Review router logs for any signs of exploitation and investigate suspicious activity
- Consider replacing affected devices with newer models if no patch becomes available
Patch Information
As of the last update on 2025-09-24, no official patch information has been released by D-Link for this vulnerability. Users should monitor the D-Link Official Website for security advisories and firmware updates. Given D-Link's history with end-of-life products, affected users should verify whether their device is still within the supported lifecycle.
Workarounds
- Disable remote management features if not required for operations
- Change the default management port and enforce strong authentication credentials
- Implement access control lists (ACLs) to limit management interface access to specific trusted IP addresses only
- Consider deploying the router behind an additional firewall that can filter malicious requests
- If the device is end-of-life, plan for replacement with a currently supported network device
For additional technical details regarding this vulnerability, refer to the VulDB entry and the GitHub PoC documentation.
Disclaimer: This content was generated using AI. While we strive for accuracy, please verify critical information with official sources.
